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JammedStab
25th Feb 2016, 21:51
This came from the same article as the Concorde supersonic shockwave thread. Has anybody ever seen or had the F/A report something like this?



"We were at 16,000 feet dodging cells at night in a Boeing 727, trying to find a safe approach into Kansas City. We were on instruments in lumpy, wet cumulus. Saint Elmo’s fire first appeared not atypically as spider webs of electricity dancing on the windshields. Soon, though, the static electricity began to extend forward from the nose of our airplane. It continued to grow and eventually was as long and as thick as a telephone pole, electricity swirling crazily around it. It was a riveting, mesmerizing display. At the same time, it caused our weather radar to fail—not a good thing when trying to steer clear of thunderstorms.

The “telephone pole” suddenly burst with a sound like someone firing a gun in the cockpit. The electrical fireworks were then gone and, thankfully, our radar had begun to function again.

Then there was a series of insistent chimes, meaning that we were being called on the intercom by a flight attendant in the cabin. “What was that?” she shouted. “What do you mean?” I asked, not realizing that anyone in the cabin had seen or heard that stunning display of Saint Elmo’s fire.

“I’ll tell you what I mean,” she blurted. “A ball of fire about six feet across came out of your cockpit, rolled its way down the aisle, disappeared in the tail, and scared the heck out of everyone back here.”

I authorized her request for complimentary beverages to be distributed to the passengers but could not tell her if TWA would pay the laundry bills."

Goldenrivett
25th Feb 2016, 22:27
Hi JammedStab,
Has anybody ever seen or had the F/A report something like this?

Yes, it is not all that unusual for people to "see" a ball of fire move.

Apparently it is caused by the eye retina receiving a very bright pulse of light (e.g. during a lightning flash.) Some of the light cones in your retina get over stimulated and when you look at something much darker, you think you can see a round red ball which appears to move as your eye scans across the dark background.

Try looking at the sun momentarily, then close your eyes. You'll "see" a round black ball.

This explains why we can see some colours better:
https://www.youtube.com/watch?v=GbHMLV4CZfI

AirUK
25th Feb 2016, 22:42
Yes, I've heard of this. Not a uncommon sight on an aircraft flying through an electrical storm I believe.

compressor stall
25th Feb 2016, 22:44
Nothing to do with optics or retinas.

Ball lightning has now been spectrally observed and also created in a lab.

There are several incidents of a hissing glowing plasma ball floating down the aisle of an aircraft.

Mad (Flt) Scientist
26th Feb 2016, 00:51
Goodness gracious.

Stanwell
26th Feb 2016, 01:21
Reported in the AvHerald:
"On December 15th 2014, Flight BE-6780 (Saab 2000) in the UK experienced ball lightning in the forward cabin just before lightning struck the aircraft's nose."

onetrack
26th Feb 2016, 01:41
"6 feet across"?? That sounds most unusual if it was actually "ball lightning" - most "ball lightning" globes are no more than 20-30cms in diameter, and many are only tennis ball sized.

There certainly have been extensively witnessed events of ball lightning inside aircraft - including one in 1963, on an aircraft full of scientists!

Ball lightning is a peculiar event that is understudied because it is so rare and unusual and short-lived.
However, there are numerous ball lightning events that have been widely reported and witnessed for many centuries. The old newspapers contain thousands of ball lightning reports, at sea and on land.

For some reason, the ball lightning appearing inside aircraft doesn't appear to have the same strength as ball lightning near the ground - where it has often been reported as having the same vicious strength as a bolt of lightning.

Below is possibly the best article on ball lightning, written by a CSIRO scientist.

Ball lightning exists - but what on earth is it? (http://theconversation.com/ball-lightning-exists-but-what-on-earth-is-it-10419)

My father and mother were witness to an amazing (ground-based) ball lightning event around early 1950. I was there at the event - but unfortunately, only in a cot! :)

In 1950, our family lived at the top of a sparsely-populated suburban street, near the top of quite a steep, high sandy hill (around 100M high) that had a ridge of very large Tuart trees scattered along the top of the ridge.
Tuart trees grow to around 30M high and can have a girth of over a metre at the butt.

It was late afternoon (probably around 6:00PM) and a sultry, stormy afternoon when Dad alighted from the bus on the main road at the bottom of the hill and commenced the 400M walk up the hill to our house.
It was still very light, as sunset is around 7:45PM at the height of Summer here.

As Dad walked up the hill, he was aware of a buzzing, crackling sound that made him turn around. He was startled to witness an outstanding example of "ball lightning" that became a much-talked about event, locally.
The event was witnessed by numerous people, including my mother, who had her face pressed to a window in the house, watching the event unfold.

According to Dad and Mum, the lightning ball travelled approximately up the centre of the street at about walking pace, at around a height of about 6 to 8M. They stated how the air "fairly crackled with electricity".
As the ball lightning passed each of the scattered houses on the street, it blew all the fuses on each house. Mum stated how she could "feel the electricity" through the window pane - enough to make her jerk back away from the glass.

They watched as the ball lightning passed our house (blowing all the fuses in the main switchboard, as it went) - then watched as it reached the top of the hill, and commenced to veer away from the road.
The ball lightning travelled directly towards one of the largest Tuart trees on the ridge - which it struck, with exactly the same effect as a lightning bolt.
The tree exploded with a massive blast that shook the house, and the tree effectively vanished!

As with any lightning strike, the tree sap had heated instantaneously and the tree virtually exploded. All that was left of the tree was a smoking stump about a metre high - and enough firewood-sized pieces of timber that kept the entire street in firewood for weeks!

The entire event lasted around 5-8 minutes - a long time, according to most witnessed ball lightning events - as most of the ball lightning events seem to only last a very short time.

Bergerie1
26th Feb 2016, 07:19
I haven't seen ball lightning but I once flew with a man who had. He said they were near thunderstorms, the was a certain amount of St Elmo's fire on the windscreen, when suddenly they saw coming towards them from right in front a ball of light. It came through the flight deck windows and then bounced sedately between the two pilots and right on down the aisle where it disappeared, presumably, out through the rear pressure bulkhead. The four men on the flight deck all saw it, as did most of the passengers and cabin crew. I have no reason to disbelieve him, he was not given to flights of fancy.

My question is; how is it possible for such a phenomenon (one would assume of an electrical nature) to penetrate a Faraday cage?

The only strange phenomenon of this kind that I have witnessed was when near thunderstorms, paralleling the ITCZ between Colombo and Kuala Lumpur. There was lightning in the vicinity and a certain amount of St Elmo's fire on the windscreen which was followed by an enormous purple cone that seemed to spread out to infinity in front of us. After a while it disappeared as suddenly as it had appeared. We weren't struck by lighnting but were much amused by the colour of the cone. We had the Anglican Bishop of Singapore on the jump seat at the time (he had asked to see the flight deck) and its colour exactly matched the colour of his shirt below his dog-collar.

ShyTorque
26th Feb 2016, 07:23
A sadly departed, ex colleague and very good friend of mine told me a very similar story to the OP's. He was flying an RAF Nimrod over the Atlantic one stormy night when the aircraft was struck by lightning. A football sized lightning ball appeared between the two pilots, drifted rear wards through the cabin then departed up inside the fin with a loud bang. He didn't personally see the ball because he was temporarily blinded. The aircraft was diverted to Newfoundland. The following morning, during an aircraft inspection, it was discovered the the front of the MAD boom had been blown off.

hoss183
26th Feb 2016, 11:59
Well the fuselage is not a perfect Faraday cage, certainly window apertures exist, and to a much lesser degree panel and door joints are also gaps in the conductive path.
I won't begin to theorise how the charge transfers internally, but perhaps the warmer drier air (than outside) provides some kind of dielectric effect.

captainsmiffy
26th Feb 2016, 12:19
I had a lightning strike in my DHC8 out of MAN, bound for ABZ. The cabin crew reported ball lightning that apparently rolled down the aisle and out through the rear of the aircraft. I never saw it, we were struck in the middle of a weather avoidance turn shortly after departure (trying to avoid the very weather that clobbered us straight after departure. ILAFFT!!)and I spent several fraught seconds trying to get instruments back on line and resetting gens etc. The flight safety manager was cock-a-hoop with our report as he had once experienced the same thing in a Canberra and, until that point, was of the opinion tht nobody ever believed him and that it was said to be a mythical thing.....

lomapaseo
26th Feb 2016, 13:30
A ball of lightning drifting down the aisle is not the time to ask it for another bag of peanuts

msbbarratt
27th Feb 2016, 06:56
As a passenger, if I'd heard a loud bang coming from the cockpit followed by a glowing ball of gas rolling down the length of the aircraft, I'd be recommending the pilots go see a dietitian as soon as possible. I'd also be holding my breath.

Clearly the regular airline food has done a lot of damage to digestive systems.

My question is; how is it possible for such a phenomenon (one would assume of an electrical nature) to penetrate a Faraday cage?

No Faraday cage is perfect, especially when it comes to RF. Screened rooms (the kind of place where one does a lot of RF testing and equipment development) have to be "tuned". They're actually double skinned, one Faraday cage inside another, with the gap in between being chosen to make the screening good over a specific frequency range.

Bergerie1
27th Feb 2016, 09:31
Thanks barratt, what you say makes eminent sense.